/Engine/Source/Runtime/Engine/Classes/Animation/AnimInstance.h
Play a Montage. Returns Length of Montage in seconds. Returns 0.f if failed to play.
float Montage_Play ( [UAnimMontage](API\Runtime\Engine\Animation\UAnimMontage) * MontageToPlay, float InPlayRate, EMontagePlayReturnType ReturnValueType, float InTimeToStartMontageAt, bool bStopAllMontages )